Ha! Very nice, but surely they wouldn’t have been able to develop a time machine without gravity would they? So, no time machine, no giant apple… and then… then… It all goes round and round, splitting universes, realities and a separate dimension⁴ of some description.

Actually this really did happen.
Newton didn’t die, he went on to start the company that provides the global supply of McD’s apple pies.
Gravity was invented later, when the law of six degrees of separation discovered the powerful draw of Kevin Bacon’s personality.
For my part, I wear a helmet in case of Mr. Bacon’s untimely demise.